1. Field of the Invention
The present invention relates generally to a jarring mechanism for use in a well bore and more specially to a jarring apparatus for use with an electric line that provides an upward jarring action to a stuck tool element suitable for use with for example an electric line.
2. Prior Art and General Background
In general, it has been found useful in an oil well or the like to use a jarring mechanism to free stuck elements. For example, see U.S. Pat. No. 1,214,622 to H. B. Walker (issued Feb. 6, 1917) in which tubing is jarred or pulled so as to shear screws to release a tubular extension of a packer from connection with a tubing or outer casing. The tubing can be now moved up and down independently of the packer and by bringing the lower closed ends of the slots of a sleeve into engagement with lugs or enlargements the packer may be jarred and jolted or lifted from its position and dislodged. It has also been found useful to use jars to impart rotational movement in an oil well. For example, U.S. Pat. No. 46,815 to Noe (issued March, 1865), discloses a jar in which one element is provided with spiral grooves and another element is provided with pins or projections which travel therein and impart relative rotational movement between the two elements. For other devices operating on similar principles, see U.S. Pat. Nos. 1,450,024 and 2,739,654. For a device which imparts rotational movement to an arbor lowered into a well on a wire line or cable by including a jar for imparting blows to the arbor in order to cause the arbor to rotate in a drag spring assembly engaged with the bore wall, see U.S. Pat. No. 3,054,454 to Evans (issued Sept. 18, 1962). The device includes cams on the arbor and a cam follower is included with the drag spring assembly for causing the rotation of the arbor when it is moved vertically with respect to the drag spring assembly.
For other patents which may be of a similar interest see, for example, U.S. Pat. No. Re. 28,768 to Mason (reissued Apr. 13, 1976) which discloses a jarring and bumping tool for use in an oil field drilling string. See also U.S. Pat. No. 2,628,820 Sheak (issued Feb. 17, 1953), which discloses a pipe puller and is related to improvements in pulling devices and more specifically to well casing pullers. For another patent which may be of interest, see U.S. Pat. No. 51,136 to Bumn (issued Nov. 28, 1865), in which a cylinder may be withdrawn by drawing a piston upward beyond its stroke, so that it will strike with a jar against a shoulder or flange allowing the cylinder to be disengaged from the outer pipe so that it may be drawn up to the top of the well.
For a patent which is directed to the problem of a pressure differential, which may exist across a tool such as a separation which is locked in place within a well casing sleeve; see U.S. Pat. No. 4,427,064 (Bowyer, issued Jan. 24, 1984). The disclosure described a no-blow tool which automatically anchors itself by means of serrated slips which are radially expandable outward into a gripping engagement with the casing and an associated wire line string in response to a rapid upward movement of a pulling tool run below the no-blow tool. The no-blow tool utilizes light, upwards jarring to free the serrated slips in order to retrieve the wire line string, and allows downward shearing of a further set of shear pins to allow a hammer to transmit downward jarring directly to the pulling tool without interference fom the slip assembly to permit the retrieval of the entire wire line tool assembly.
Another oil field procedure or operation which may result in a tool becoming stuck in a well bore are commonly termed electric line operations such as open hole well logging, cased hole logging, dipmeter, side wall cores, perforating, "Baker" setting tools and RFT tools. Examples of open hole well logging tools include, for example, "ISF-Sonic" and "Densilog" and examples of cased hole tools include, for example, "CBL-VDL" and "Neutron Lifetime Log."
With these types of operations, an electric line tool would be generally lowered into a well bore with the tool connected to the lower end of the electric line. While being lowered, the tool may stick for various reasons including, for example, differential sticking, which is caused by a pressure differential between a higher pressure in the well bore and a lower pressure in the surrounding formation. This may generally cause the tool to be sucked against the bore wall by the pressure differential, resulting in a differentially stuck tool.
This condition may be alleviated, for example, by lowering the mud weight to reduce the pressure differential and aid in freeing the stuck tool. However under certain conditions the tool will still remain stuck to the side of the well bore.
Another example of sticking would be pads which extend outward from logging tools digging in and becoming stuck in a void along the bore wall. Once stuck, the tool may be unstuck by increasing the hoisting force. However, in some instances the connection between the tool and the elecric line may not be able to withstand an increased hoist force sufficient to unstick the tool, and an attempt to increase the hoisting force may only pull the electric line loose from the tool, necessitating going into the hole with fishing tools to retrieve the stuck tool.
Prior to this invention it was apparently not known or considered feasible to employ a jarring apparatus with an electric line operation to free an electric line tool. Applicants know of no concept which allows jarring to be used with an electric line, and it is to this problem that the present invention is directed.
Further, so far as known to applicants, the prior art discloses no arrangement which is suitable for providing upward jarring to an electric line tool element which has become stuck in a well bore.
3. General, Summary Discussion of the Invention
It is an object of the invention of the present method and apparatus is to provide a new method and apparatus suitable for use with an electric line for jarring loose a tool element, which is stuck in a well, by a quick, generally upward motion of an electric line. In accordance with this object, it is an object of the method and apparatus of the invention that the jarring provide an upward jarring action to loosen the stuck tool element.
It is a further object of the present method and apparatus or system of the present invention that the motion of the electric line may be reciprocal to provide a series of jarring actions to loosen the stuck tool element.
Accordingly, it is a feature of the present invention that the electric line be disconnected from the tool element responsive to a first predetermined force in the electric line, while remaining in attached configuration to a hammer which is released from a first configuration by a second predetermined force in the electric line to move upwards by the quick, generally upward motion of the electric line to a second configuration to strike a spaced anvil to provide the upward jarring action which is transmitted to the stuck tool element.
A further object of the method and apparatus or system of the present invention is to provide a means for releasing the tool element from the apparatus responsive to a third predetermined force in the electric line which is higher than the first predetermined force and the second predetermined force. In accordance with this object, the electric line, which may include portions of the apparatus of the present invention, may be withdrawn from the well, allowing fishing tools to be used to remove the stuck tool element.
In accordance with this object, a means which retains the hammer in its first configuration aids in absorbing the initial rapid upward motion of the hammer as it moves toward its second configuration to restrain premature releasing of the means for releasing the tool element from the apparatus.
A further object of the method and apparatus of the present invention is to provide an arrangement suitable for a series of jarring actions to loosen the stuck tool element. In accordance with this object, it is a feature of the present invention that the hammer may be returned to a lower configuration which may be the same as the first configuration responsive to the lowering of the electric line, and that a further quick, generally upward motion of the electric line move the hammer upward toward the second configuration, so that a series of upward jarring actions may be made which may be transmitted to loosen the stuck tool element.
In accordance with these objects, the arrangement includes a tubular member disposed in a well with a tool element disposed below and attached thereto, a hammer which is moveable upwards from a first configuration to a second configuration by a generally quick, upward motion of an electric line to strike an opposed, spaced anvil to provide a generally upward jarring action to jar the element, means for transferring the upward jarring action from the anvil to the element and jar the element in a generally upward direction, means for leaving the tool element disposed in the well below a tubular member in its attached configuration with the tubular member, and means for disconnecting the electric line from the tool element responsive to a first generally upward force in the electric line.
Accordingly, the arrangement further includes a cylindrical rod slidably disposed in the tubular member having a central longitudinal bore therethrough with the electric line extending through its bore and connected at its lower end to the tool element, means associated with the cylindrical rod and the tubular member for releasing the cylindrical rod from a first configuration responsive to a second predetermined force in the electric line, and means responsive to a generally upward motion of the electric line for moving the cylindrical rod from a first configuration in the tubular member to a second configuration. In further accordance, the hammer is attached to the cylindrical rod for motion therewith by the upward motion of the electric line toward the opposed spaced anvil, and the opposed anvil is fixedly attached to the tubular member, the quick, generally upward motion of the cylindrical rod from its first configuration to its second configuration moving the hammer to strike against the anvil and provide a generally upward jarring action.
In accordance, the first configuration is a lower configuration and the second configuration is an upper configuration, the motion of the electric line may be reciprocal, and the arrangement includes a means for moving the cylindrical rod downward from its second configuration responsive to a downward motion of said electric line to a further lower configuration which may be the same as the first configuration. Thus, the reciprocal motion of the electric line provides a means for a reciprocal motion of the rod and hammer, so that the reciprocal motion of the hammer provides a series of jarring actions.